Musically, the worst case example that comes to mind is SPK. Can't even begin to fathom how a band responsible for such visceral, abrasive music, and who fully deserve their rep as industrial pioneers, went from the sonic assault of 'Information Overload Unit' to the abysmal, desperate-for-a-hit wankfest that's 'Machine Age Voodoo' in the space of just over two years. The Thompson Twins have more in common with Throbbing Gristle than that pile of shit album has with anything SPK released pre-'83.

Sometime around 2000/2001, a friend purchased a live VHS tape of a then-recent Shabba Ranks performance...in a Jamaican church hall. After 45 mins of 'WTF is this?' child gospel performers, Shabba shambles onto the stage, looking totally spangled - no, actually, in pain - and delivers a performance so tortured (accentuated by the cheap shaky-cam) that it felt like rubbernecking at someone having a breakdown. I know he's got himself back on track, but that was a true Spinal Tap-style moment I'd rather have not witnessed.

Not as bad as those two, but I also lament Coil's downward trajectory from 'urban warlocks doing MDMA in the bogs at Heaven' to the coast-dwelling bores who inspired the whole wretched Ghostbox genre.